For the most part, the background of the invention is fully described in the patent incorporated by reference.
As seen the bar of the invention is normally a hollow extrusion of aluminum having a square cross section secured by a hinged pivot to the vertical frame of a patio door opening and normally arranged for storage parallel with said vertical frame. When stored thusly, the panel of heavy glass which slides in the opening can be moved freely towards the vertical frame, the opening being twice the size of the glass panel and there being a second fixed panel which the first panel overlies when the access is given through the opening to the building or out of the building in which the patio doors are installed. It is appreciated that even in opened condition half of the large opening is still covered; both panels blocking the opening when the doors are in closed condition.
The bar is stored vertically and when swung to a blocking position is rotated in a clockwise direction if the hinge is considered to be on the viewers left. This brings the free end down into the bight of a U-shaped bracket where it rests. To remove the bar from its horizontal blocking condition, one raises the free end out of the bight of the U-shaped bracket.
Complete security cannot be achieved if access can be had to the interior of the patio doors, either by an intruder actually entering or by such intruder slipping a wire or other instrumentality through a crevice from the exterior of the patio doors into the interior and hooking its bent end around the bar and raising it out of the bight of the U-shaped bracket. Additionally small children can readily raise the bar from the interior of the house to enable them to open the patio doors without parental authority.
The invention obviates these problems by providing a lock for the bar which is adapted to be operated by means of a tool such as a key from the interior of the doors.
While sounding simple, the problems of providing a lock for the kind of security bar here involved is not readily capable of solution for a variety of reasons. Some of these are listed below:
1. The width of patio door panels vary from structure to structure making it well nigh impossible to install a lock on the bars as manufactured, hence there must be some way for the lock to be installed by an amateur or a workman in the field. The installation must be effective to have any value and hence the arrangement must be foolproof.
2. The lock arrangement must be capable of being installed on existing security bars without the need for taking the system apart, or at least without requiring substantial substitution of parts.
3. It was considered that great advantages could be effected if the entire mechanism could be substantially contained within the bar itself, but since these bars are for the most part commercially made out of 5/8 inch outer diameter square tubing with the hollow interior having an interior dimension of one half inch, the solution to the problem is not obvious.
4. The lock arrangement is required to be extremely simple to manufacture and install and additionally is required to be economical for the user to purchase.
The invention achieves a solution to all of these problems in a structure which can be sold in kit form as parts to be installed into the end of a bar without doing anything to the bar other than drilling a hole in the side wall of the bar or in the form of a short bar section that is coupled to the end of an existing bar after the free end of the bar has been shortened by sawing it off. In both cases, in addition to the single hole required to be drilled in the side wall of the bar another hole is required to be drilled in the jamb of the sliding door. In some cases the bar may be carried by the jamb and the free end is to be engaged at the door frame in which case the hole to receive the bolt of the lock is drilled in the frame. This hole is called a bolt end receiving socket in the specification.